Input screen of an image intensifier

Claim 2

An input screen of an image intensifer for converting incident radiation into electrons, comprising an aluminium substrate provided with a mosaic surface prepared by anodizing, sealing process and heat treatment, said mosaic surface including a porous layer of aluminium oxide on said surface formed by said anodizing and sealing process and a large number of narrow grooves and numerous islands defined by said narrow grooves; a fluorescent layer formed on the aluminium oxide layer as crystals and having cracks above the narrow grooves and a large number of columnar blocks defined by the cracks which are arranged substantially parallel with each other; and a photocathode provided on said fluorescent layer.

Claim 3

The input screen according to claim 1, wherein a thin barrier layer is provided between the fluorescent layer and photocathode to prevent the composition of the photocathode from being absorbed in the fluorescent layer.

Claim 4

The input screen according to claim 2, wherein the thin barrier layer is made of one selected from the group consisting of alumina and silica.

Claim 5

The input screen according to claim 1, wherein the fluorescent layer is formed of cesium iodide.

Claim 6

An input screen of an image intensifier for converting incident radiation into electrons, comprising an aluminium substrate provided with a mosaic surface, said mosaic surface including a large number of narrow grooves and numerous islands defined by said narrow grooves the width W and depth D of the narrow grooves formed in the mosaic surface of the aluminium substrate and the thickness T of the fluorescent layer having such measurements to satisfy the following equations: T=AW+B D≧W/2 where A=30; -65μ≦B≦45μ; T≧50μ; and 1μ≦W≦15μ, a fluorescent layer formed on the aluminium and having cracks above the narrow grooves and a large number of columnar blocks defined by the cracks which are arranged substantially parallel with each other; and a photocathode provided on said fluorescent layer.

Claim 7

An input screen of an image intensifier for converting incident radiation into electrons, comprising an aluminium substrate provided with a mosaic surface, said mosaic surface including a large number of narrow grooves and numerous islands defined by said narrow grooves the width W and depth D of the narrow grooves formed in the mosaic surface of the aluminium substrate and the thickness T of the fluorescent layer having such measurements to satisfy the following equations: T=AW+B D≧W/2 where A=30; -65μ≦B≦45μ; T≧50μ; and 1μ≦W≦15μ, a fluorescent layer formed on the aluminium and having cracks above the narrow grooves and a large number of columnar blocks defined by the cracks which are arranged substantially parallel with each other; and a photocathode provided on said fluorescent layer.

Claim 8

The input screen according to claim 1, wherein a reflection layer is mounted on the mosaic surface of the aluminium substrate which faces the fluorescent layer.

Claim 9

The input screen according to claim 1, wherein a light-absorbing layer is formed on the mosaic surface of the aluminium substrate which faces the fluorescent layer.

Claim 10

The input screen according to claim 1, wherein the fluorescent layer a barner layer for connecting together the columnar blocks in the proximity of the photocathode.